1. Field of the Invention
The present invention relates to the enhancement of discharge properties and endurance of lead-acid battery.
2. Description of the Related Art
A lead-acid battery has been widely applied as an inexpensive reliable high safety secondary battery for SLI (Starting, Lighting and Ignition) and other purposes. However, a lead-acid battery has a low specific energy that gives a serious obstacle to the development of its application to EV (electric vehicle), etc.
Many methods have long been studied to enhance the specific energy of lead-acid battery. One of these proposed methods is to add tin in the positive active material to enhance the discharge properties of the lead-acid battery. However, this approach is disadvantageous in that tin thus added is eluted from the positive active material with the electrolyte and then deposited on the negative plate to lower the hydrogen overvoltage of the negative plate and hence cause much lead sulfate to be accumulated on the negative plate, thereby reducing the endurance of the lead-acid battery.